Deployment of Internet of Things (IoT) relies on networks of low-cost wireless devices that work reliably in the presence of interference. IoT standards include, for example, IEEE standard 802.15.4 (used by low power energy Bluetooth (BLE), Zigbee, and Thread standards). These standards use pseudo noise (PN) coding sequences over O-QPSK (offset quadrature phase shift keying. While a preamble may be used for symbol timing and frequency acquisition, the frame delimiter needs to be detected separately. Because noisy signals may create false detections, techniques that are more robust to noisy environments are important.
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